Adds krt_source route attribute.

Thanks Jeremie Dimino for the original patch.

doc/bird.sgml

@@ -1653,6 +1653,12 @@ are translated to appropriate system (and OS-specific) route attributes.
 We support these attributes:
 
 <descrip>
+	<tag>int <cf/krt_source/</tag> The source of the imported
+	kernel route.  The value is system-dependent. On Linux, it is
+	a value of the protocol field of the route. See
+	/etc/iproute2/rt_protos for common values.  On BSD, it is
+	based on STATIC and PROTOx flags. The attribute is read-only.
+
 	<tag>ip <cf/krt_prefsrc/</tag> (Linux) The preferred source address.
  	Used in source address selection for outgoing packets. Have to
  	be one of IP addresses of the router.

sysdep/bsd/krt-sock.c

@@ -255,10 +255,11 @@ krt_read_rt(struct ks_msg *msg, struct krt_proto *p, int scan)
   ip_addr idst, igate, imask;
   void *body = (char *)msg->buf;
   int new = (msg->rtm.rtm_type == RTM_ADD);
-  int src;
   char *errmsg = "KRT: Invalid route received";
   int flags = msg->rtm.rtm_flags;
   int addrs = msg->rtm.rtm_addrs;
+  int src;
+  byte src2;
 
   if (!(flags & RTF_UP) && scan)
     SKIP("not up in scan\n");
@@ -302,12 +303,17 @@ krt_read_rt(struct ks_msg *msg, struct krt_proto *p, int scan)
   u32 self_mask = RTF_PROTO1;
   u32 alien_mask = RTF_STATIC | RTF_PROTO1 | RTF_GATEWAY;
 
+  src2 = (flags & RTF_STATIC) ? 1 : 0;
+  src2 |= (flags & RTF_PROTO1) ? 2 : 0;
+
 #ifdef RTF_PROTO2
   alien_mask |= RTF_PROTO2;
+  src2 |= (flags & RTF_PROTO2) ? 4 : 0;
 #endif
 
 #ifdef RTF_PROTO3
   alien_mask |= RTF_PROTO3;
+  src2 |= (flags & RTF_PROTO3) ? 8 : 0;
 #endif
 
 #ifdef RTF_REJECT
@@ -397,9 +403,9 @@ krt_read_rt(struct ks_msg *msg, struct krt_proto *p, int scan)
   e = rte_get_temp(&a);
   e->net = net;
   e->u.krt.src = src;
+  e->u.krt.proto = src2;
 
   /* These are probably too Linux-specific */
-  e->u.krt.proto = 0;
   e->u.krt.type = 0;
   e->u.krt.metric = 0;
 

sysdep/unix/krt.Y

@@ -17,7 +17,7 @@ CF_DEFINES
 
 CF_DECLS
 
-CF_KEYWORDS(KERNEL, PERSIST, SCAN, TIME, LEARN, DEVICE, ROUTES)
+CF_KEYWORDS(KERNEL, PERSIST, SCAN, TIME, LEARN, DEVICE, ROUTES, KRT_SOURCE)
 
 CF_GRAMMAR
 
@@ -90,6 +90,8 @@ kif_item:
    }
  ;
 
+CF_ADDTO(dynamic_attr, KRT_SOURCE { $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_INT, EA_KRT_SOURCE); })
+
 CF_CODE
 
 CF_END

sysdep/unix/krt.c

@@ -907,12 +907,29 @@ krt_shutdown(struct proto *P)
   return PS_DOWN;
 }
 
+struct ea_list *
+krt_make_tmp_attrs(struct rte *rt, struct linpool *pool)
+{
+  struct ea_list *l = lp_alloc(pool, sizeof(struct ea_list) + 1 * sizeof(eattr));
+
+  l->next = NULL;
+  l->flags = EALF_SORTED;
+  l->count = 1;
+  l->attrs[0].id = EA_KRT_SOURCE;
+  l->attrs[0].flags = 0;
+  l->attrs[0].type = EAF_TYPE_INT | EAF_TEMP;
+  l->attrs[0].u.data = rt->u.krt.proto;
+
+  return l;
+}
+
 static struct proto *
 krt_init(struct proto_config *c)
 {
   struct krt_proto *p = proto_new(c, sizeof(struct krt_proto));
 
   p->p.accept_ra_types = RA_OPTIMAL;
+  p->p.make_tmp_attrs = krt_make_tmp_attrs;
   p->p.import_control = krt_import_control;
   p->p.rt_notify = krt_notify;
 
@@ -952,12 +969,18 @@ krt_get_attr(eattr * a, byte * buf, int buflen UNUSED)
 {
   switch (a->id)
   {
+  case EA_KRT_SOURCE:
+    bsprintf(buf, "source");
+    return GA_NAME;
+
   case EA_KRT_PREFSRC:
     bsprintf(buf, "prefsrc");
     return GA_NAME;
+
   case EA_KRT_REALM:
     bsprintf(buf, "realm");
     return GA_NAME;
+
   default:
     return GA_UNKNOWN;
   }

sysdep/unix/krt.h

@@ -28,8 +28,9 @@ struct kif_proto;
 #define KRF_DELETE 3			/* Should be deleted */
 #define KRF_IGNORE 4			/* To be ignored */
 
-#define EA_KRT_PREFSRC EA_CODE(EAP_KRT, 0)
-#define EA_KRT_REALM EA_CODE(EAP_KRT, 1)
+#define EA_KRT_SOURCE	EA_CODE(EAP_KRT, 0)
+#define EA_KRT_PREFSRC	EA_CODE(EAP_KRT, 1)
+#define EA_KRT_REALM	EA_CODE(EAP_KRT, 2)
 
 /* Whenever we recognize our own routes, we allow learing of foreign routes */
 

sysdep/unix/main.c

@@ -191,7 +191,7 @@ sysdep_preconfig(struct config *c)
   init_list(&c->logfiles);
 
 #ifdef PATH_IPROUTE_DIR
-  // read_iproute_table(PATH_IPROUTE_DIR "/rt_protos", "ipp_", 256);
+  read_iproute_table(PATH_IPROUTE_DIR "/rt_protos", "ipp_", 256);
   read_iproute_table(PATH_IPROUTE_DIR "/rt_realms", "ipr_", 256);
   read_iproute_table(PATH_IPROUTE_DIR "/rt_scopes", "ips_", 256);
   read_iproute_table(PATH_IPROUTE_DIR "/rt_tables", "ipt_", 256);